The use of reciprocating mechanisms on fishing reels to effect controlled winding of line on associated spools is known. These mechanisms are referred to in the art as oscillation systems. Prior art oscillation systems are based on cammed, geared, or lead-screw driven mechanisms that are linked in a variety of manners to the turning of the fishing reel handle. The present invention employs the lead-screw actuation method. Accordingly, other oscillation methods will not be discussed.
Lead-screw oscillation systems share a common characteristic in that they all have an eared pawl slidably engaged to a lead-screw defined by a recessed track integral to a rotating shaft. The ears of the pawl travel within and are guided by the track such that as the lead-screw rotates, the oscillation pawl is forced to move reciprocally and in fixed radial alignment to the lead-screw as the lead-screw shaft rotates.
Prior art lead-screw devices employ many different methods, but generally link lead-screw rotation with the turning of the reel handle. These prior art methods are usually complicated and expensive to manufacture. U.S. Pat. No. 4,773,611 issued to Kaneko teaches a conventional lead-screw oscillation system. The accepted advantages of lead-screw oscillation systems, however, justify their usual cost and complexity.
The majority of known lead-screw oscillation systems employ a rotating lead-screw as described above. There is no mechanical dictate in lead-screw oscillation designs, however, for the lead-screw to rotate while the pawl moves axially along the lead-screw. Accordingly, it is mechanically acceptable to have a pawl rotate around a sliding, non-rotating lead-screw to effect the same reciprocating movement. Such a prior art fishing reel is disclosed in U.S. Pat. No. 4,618,107 issued to Nakajima. Nakajima teaches the use of a rotating pawl that moves about a sliding, non-rotating lead-screw. To this end, Nakajima teaches the use of a first drive mechanism to rotate the pawl around the oscillation drive track to effect oscillation and a second drive mechanism to turn the rotor to wind the line around the spool. The additional components of the separate drive mechanisms add to the complexity and cost of the reel.
Therefore, it can be appreciated that a need exists for a new fishing reel oscillation system having a low cost design and ease of manufacture while maintaining all the accepted advantages of conventional lead-screw oscillation designs. More specifically, a need exists for a rotating pawl lead-screw oscillation system that obviates the need for separate oscillation assemblies required by prior art designs.